public static void main(String[] args) throws Exception {
		// TODO Auto-generated method stub
		File saveFile = new File("a");
//		RandomAccessFile accessFile = new RandomAccessFile(saveFile, "rwd");
//		accessFile.close();
		RandomAccessFile accessFile1 = new RandomAccessFile(saveFile, "rwd");
		accessFile1.writeChars("4454545");
		accessFile1.close();
	}

?

对于这句代码说明：

RandomAccessFile accessFile1 = new RandomAccessFile(saveFile, "rwd");

?

不管怎样，都对saveFile这个文件进行随机读写的,如果不存在saveFile文件，就会自动创建一个空白文件的!